Add a checksum to the generated QML compilation units

Change-Id: Icd5b1d805059981cbbb4c0eb2a5c842d59223839
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

8 files changed, 45 insertions, 6 deletions

diff --git a/src/qml/compiler/qqmlirbuilder.cpp b/src/qml/compiler/qqmlirbuilder.cpp
index f736e04b88..31250d0d57 100644
--- a/src/qml/compiler/qqmlirbuilder.cpp
+++ b/src/qml/compiler/qqmlirbuilder.cpp
@@ -1359,7 +1359,7 @@ bool IRBuilder::isRedundantNullInitializerForPropertyDeclaration(Property *prope
     return QQmlJS::AST::cast<QQmlJS::AST::NullExpression *>(expr);
 }
 
-QV4::CompiledData::Unit *QmlUnitGenerator::generate(Document &output)
+QV4::CompiledData::Unit *QmlUnitGenerator::generate(Document &output, QQmlEngine *engine, const QV4::CompiledData::ResolvedTypeReferenceMap &dependentTypes)
 {
     QQmlRefPointer<QV4::CompiledData::CompilationUnit> compilationUnit = output.javaScriptCompilationUnit;
     QV4::CompiledData::Unit *jsUnit = compilationUnit->createUnitData(&output);
@@ -1402,6 +1402,20 @@ QV4::CompiledData::Unit *QmlUnitGenerator::generate(Document &output)
     qmlUnit->offsetToStringTable = totalSize - output.jsGenerator.stringTable.sizeOfTableAndData();
     qmlUnit->stringTableSize = output.jsGenerator.stringTable.stringCount();
 
+#ifndef V4_BOOTSTRAP
+    if (!dependentTypes.isEmpty()) {
+        QCryptographicHash hash(QCryptographicHash::Md5);
+        if (dependentTypes.addToHash(&hash, engine)) {
+            QByteArray checksum = hash.result();
+            Q_ASSERT(checksum.size() == sizeof(qmlUnit->dependencyMD5Checksum));
+            memcpy(qmlUnit->dependencyMD5Checksum, checksum.constData(), sizeof(qmlUnit->dependencyMD5Checksum));
+        }
+    }
+#else
+    Q_UNUSED(dependentTypes);
+    Q_UNUSED(engine);
+#endif
+
     // write imports
     char *importPtr = data + qmlUnit->offsetToImports;
     foreach (const QV4::CompiledData::Import *imp, output.imports) {
diff --git a/src/qml/compiler/qqmlirbuilder_p.h b/src/qml/compiler/qqmlirbuilder_p.h
index 821a6bba6d..eedc262e7a 100644
--- a/src/qml/compiler/qqmlirbuilder_p.h
+++ b/src/qml/compiler/qqmlirbuilder_p.h
@@ -549,7 +549,7 @@ public:
 
 struct Q_QML_PRIVATE_EXPORT QmlUnitGenerator
 {
-    QV4::CompiledData::Unit *generate(Document &output);
+    QV4::CompiledData::Unit *generate(Document &output, QQmlEngine *engine, const QV4::CompiledData::ResolvedTypeReferenceMap &dependentTypes);
 
 private:
     typedef bool (Binding::*BindingFilter)() const;
diff --git a/src/qml/compiler/qqmltypecompiler.cpp b/src/qml/compiler/qqmltypecompiler.cpp
index a0b219e28e..68de9aee44 100644
--- a/src/qml/compiler/qqmltypecompiler.cpp
+++ b/src/qml/compiler/qqmltypecompiler.cpp
@@ -156,7 +156,7 @@ QV4::CompiledData::CompilationUnit *QQmlTypeCompiler::compile()
     // Generate QML compiled type data structures
 
     QmlIR::QmlUnitGenerator qmlGenerator;
-    QV4::CompiledData::Unit *qmlUnit = qmlGenerator.generate(*document);
+    QV4::CompiledData::Unit *qmlUnit = qmlGenerator.generate(*document, QQmlEnginePrivate::get(engine), resolvedTypes);
 
     Q_ASSERT(document->javaScriptCompilationUnit);
     // The js unit owns the data and will free the qml unit.
diff --git a/src/qml/compiler/qv4compileddata.cpp b/src/qml/compiler/qv4compileddata.cpp
index 2aab1743cc..83ae9c56df 100644
--- a/src/qml/compiler/qv4compileddata.cpp
+++ b/src/qml/compiler/qv4compileddata.cpp
@@ -579,6 +579,19 @@ void ResolvedTypeReference::doDynamicTypeCheck()
         mo = compilationUnit->rootPropertyCache()->firstCppMetaObject();
     isFullyDynamicType = qtTypeInherits<QQmlPropertyMap>(mo);
 }
+
+bool ResolvedTypeReferenceMap::addToHash(QCryptographicHash *hash, QQmlEngine *engine) const
+{
+    for (auto it = constBegin(), end = constEnd(); it != end; ++it) {
+        QQmlPropertyCache *pc = it.value()->createPropertyCache(engine);
+        bool ok = false;
+        hash->addData(pc->checksum(&ok));
+        if (!ok)
+            return false;
+    }
+    return true;
+}
+
 #endif
 
 }
diff --git a/src/qml/compiler/qv4compileddata_p.h b/src/qml/compiler/qv4compileddata_p.h
index 82e303f27d..519708f089 100644
--- a/src/qml/compiler/qv4compileddata_p.h
+++ b/src/qml/compiler/qv4compileddata_p.h
@@ -611,6 +611,7 @@ struct Unit
 
     LEUInt32 architectureIndex; // string index to QSysInfo::buildAbi()
     LEUInt32 codeGeneratorIndex;
+    char dependencyMD5Checksum[16];
 
     enum : unsigned int {
         IsJavascript = 0x1,
@@ -788,7 +789,14 @@ struct ResolvedTypeReference
     void doDynamicTypeCheck();
 };
 // map from name index
-typedef QHash<int, ResolvedTypeReference*> ResolvedTypeReferenceMap;
+// While this could be a hash, a map is chosen here to provide a stable
+// order, which is used to calculating a check-sum on dependent meta-objects.
+struct ResolvedTypeReferenceMap: public QMap<int, ResolvedTypeReference*>
+{
+    bool addToHash(QCryptographicHash *hash, QQmlEngine *engine) const;
+};
+#else
+struct ResolvedTypeReferenceMap {};
 #endif
 
 // index is per-object binding index
diff --git a/src/qml/compiler/qv4compiler.cpp b/src/qml/compiler/qv4compiler.cpp
index 768a4ffcd3..8503317430 100644
--- a/src/qml/compiler/qv4compiler.cpp
+++ b/src/qml/compiler/qv4compiler.cpp
@@ -361,6 +361,7 @@ QV4::CompiledData::Unit QV4::Compiler::JSUnitGenerator::generateHeader(QV4::Comp
     unit.qtVersion = QT_VERSION;
     unit.architectureIndex = registerString(QSysInfo::buildAbi());
     unit.codeGeneratorIndex = registerString(codeGeneratorName);
+    memset(unit.dependencyMD5Checksum, 0, sizeof(unit.dependencyMD5Checksum));
 
     quint32 nextOffset = sizeof(CompiledData::Unit);
 
diff --git a/src/qml/qml/qqmltypeloader.cpp b/src/qml/qml/qqmltypeloader.cpp
index c54af43a6f..9f94aa41ec 100644
--- a/src/qml/qml/qqmltypeloader.cpp
+++ b/src/qml/qml/qqmltypeloader.cpp
@@ -2910,7 +2910,8 @@ void QQmlScriptBlob::dataReceived(const Data &data)
         irUnit.unitFlags |= QV4::CompiledData::Unit::IsSharedLibrary;
 
     QmlIR::QmlUnitGenerator qmlGenerator;
-    QV4::CompiledData::Unit *unitData = qmlGenerator.generate(irUnit);
+    QV4::CompiledData::ResolvedTypeReferenceMap emptyDependencies;
+    QV4::CompiledData::Unit *unitData = qmlGenerator.generate(irUnit, m_typeLoader->engine(), emptyDependencies);
     Q_ASSERT(!unit->data);
     // The js unit owns the data and will free the qml unit.
     unit->data = unitData;
diff --git a/src/qml/qml/qqmltypeloader_p.h b/src/qml/qml/qqmltypeloader_p.h
index ab6b046fcf..5f754df1fc 100644
--- a/src/qml/qml/qqmltypeloader_p.h
+++ b/src/qml/qml/qqmltypeloader_p.h
@@ -463,7 +463,9 @@ private:
     QList<TypeReference> m_compositeSingletons;
 
     // map from name index to resolved type
-    QHash<int, TypeReference> m_resolvedTypes;
+    // While this could be a hash, a map is chosen here to provide a stable
+    // order, which is used to calculating a check-sum on dependent meta-objects.
+    QMap<int, TypeReference> m_resolvedTypes;
     bool m_typesResolved:1;
 
     QQmlRefPointer<QV4::CompiledData::CompilationUnit> m_compiledData;